Prior art augmented reality devices are shown in FIG. 1 and FIG. 2. FIG. 1 illustrates that a shell of the augmented reality device is a box. A mobile phone is placed in the box to use functions of the augmented reality device. FIG. 2 illustrates the augmented reality device when worn. But the shell of the augmented reality device in FIG. 1 and FIG. 2 is not sealed. When the augmented reality device is outside in the rain, the augmented reality device can be damaged.